Using a droid x and the latest version of the client, I'm finding that if I switch apps while using waze (take a phone call on bluetooth, check my twitter notifications at a red light), when I return to waze my map is now missing the roads. All my goodies show up, the water features and street names show up, and the map rotates as necessary, but the roads are now gone.
I can fix this by exiting and rebooting waze, but this becomes a hassle. Is anyone else having this issue? I'll try to take a screen shot later tonight when I have the time to figure it out.